feat(ai): integrate local Ollama AI for in-context sentence translation and caching (Task 13)

tests/test_api.py

@@ -1206,3 +1206,69 @@ def test_offline_dictionary_lookup_and_coverage():
     asyncio.run(run_lookups())
 
 
+def test_sentence_translation_ai_and_caching():
+    """Validates local AI sentence translation endpoint, SQLite caching, and in-context word meaning."""
+    import time
+    from app.database import compute_sentence_hash, get_cached_sentence_translation, save_sentence_translation
+
+    # 1. Unauthenticated request must be blocked
+    client.cookies.clear()
+    unauth_res = client.post("/api/translate-sentence", json={"sentence": "He had a prodigious memory."})
+    assert unauth_res.status_code == 401
+
+    # 2. Login as admin
+    login_res = client.post("/api/login", json={"username": "testadmin", "password": "testpass12345"})
+    assert login_res.status_code == 200
+
+    # 3. Empty sentence validation
+    empty_res = client.post("/api/translate-sentence", json={"sentence": "   "})
+    assert empty_res.status_code == 400
+
+    # 4. Direct SQLite cache unit test
+    sentence = "He took the matter into his own hands and succeeded."
+    target_word = "matter"
+    h = compute_sentence_hash(sentence, target_word)
+    assert len(h) == 64
+
+    # Initially not cached
+    assert get_cached_sentence_translation(sentence, target_word) is None
+
+    # Save to cache
+    save_sentence_translation(
+        sentence=sentence,
+        translated_text="Он взял дело в свои руки и преуспел.",
+        target_word=target_word,
+        word_meaning="дело, вопрос",
+        source="unit_test",
+    )
+
+    cached_entry = get_cached_sentence_translation(sentence, target_word)
+    assert cached_entry is not None
+    assert cached_entry["translated_text"] == "Он взял дело в свои руки и преуспел."
+    assert cached_entry["word_meaning"] == "дело, вопрос"
+    assert cached_entry["source"] == "unit_test"
+
+    # 5. Fast cached retrieval via HTTP endpoint (< 10ms)
+    t0 = time.perf_counter()
+    api_res = client.post(
+        "/api/translate-sentence",
+        json={"sentence": sentence, "target_word": target_word},
+    )
+    dt_ms = (time.perf_counter() - t0) * 1000
+    assert api_res.status_code == 200
+    data = api_res.json()
+    assert data["cached"] is True
+    assert data["sentence_ru"] == "Он взял дело в свои руки и преуспел."
+    assert data["word_meaning"] == "дело, вопрос"
+    assert dt_ms < 50.0
+
+    # 6. Test AI status endpoint
+    status_res = client.get("/api/ai/status")
+    assert status_res.status_code == 200
+    status_data = status_res.json()
+    assert "online" in status_data
+    assert "models" in status_data
+    assert "active_model" in status_data
+
+
+